C Caller
Integrate C code in Simulink
Libraries:
Simulink /
User-Defined Functions
Description
The C Caller block integrates your external C code into Simulink®. This block imports and lists the functions in your external C code, and enables you to select your resolved C functions to integrate in your Simulink models. The C Caller block standalone supports code generation. For more complex models, code generation depends on the capabilities of your Simulink model.
To use the C Caller block, define your source code and any supporting files
using Simulation Target under Configuration
Parameters. Then, bring a C Caller block to the Simulink canvas, using Library Browser > Simulink > User Defined Functions. To change the defined source code file and its dependencies, go to
Simulation Target tab in Configuration
Parameters by clicking the 
from the block dialog. After changing your source code or any
of its dependencies, refresh the list of functions by clicking the 
on the block dialog. To browse the function definitions in
your source code, use the 
icon to access your source files.
You can use the addGlobalArg
function to add global variables from custom code as global arguments to the block, or use the
deleteGlobalArg
function to delete global arguments from the block. (since R2024b)
Examples
Use Simulink Strings for C Caller Block
How to use Simulink Strings for C Caller block.
Call Custom C Functions in Simulink Using C Caller Block
Call and integrate custom C function that performs arithmetic operations into Simulink.
Call C Function Containing C Structure into Simulink
Call and integrate custom C function that performs bus operations into Simulink.
Call C Function Containing Enumerated Data Type into Simulink
Map enumerated data type from custom C code into Simulink using a C Caller block.
Ports
Input
Output
Parameters
Name of the function parsed for the C Caller block, specified as a character vector or string scalar. For a list of available functions, see Available Functions.
Tunable: Yes
Programmatic Use
Block Parameter:
FunctionName |
| Type: character vector or string scalar |
myFunctionName = get_param(gcb,"FunctionName")myFunctionName =
'mean_filter'Port properties, specified as a table. The table indicates the attributes of each
input and output element of the block. If the scope is an
input, you can modify this variable to a
parameter or a constant. These
properties include
Name — Demonstrates the variable name inferred from your source code.
A bold argument name indicates that the port or parameter is a global argument.
Scope — Indicates the role of the variables from your source code. If the variable is an input argument in the C Caller block source code, you can change the scope type to a constant or a parameter. If the variable is an output argument in the source code, you cannot change the scope type.
Label — Labels the input or output variable for the Simulink model. You can change the labels using this table. If the scope is a parameter, enter the parameter name in this field. If the scope is a constant, enter the constant value.
Type — Indicates the data type coming from the ports.
Size — Indicates the size of the input and output data.
Name, scope, type, and size are inferred from your source code.
Programmatic Use
Block Parameter:
FunctionPortSpecification |
Type:
FunctionPortSpecification object |
List of all available functions that can be mapped to a C Caller block, specified as a cell array.
The C Caller block in your model imports all functions in your
external source code, and shows the function names next to the Function name on the block
dialog. To select and use a function in your block, confirm that the function name
appears in the Available Functions table. If you are missing
one of the functions, reload the source code by clicking on the block dialog. To change the names of functions,
modify your source code and click the Refresh button to reload.
Programmatic Use
Block Parameter:
AvailableFunctions |
| Type: cell array |
allAvailableFunctions = get_param(gcb, "AvailableFunctions")allAvailableFunctions =
1×1 cell array
{'add'}
Sample period, specified in seconds. See Types of Sample Time and Specify Sample Time.
Programmatic Use
Block Parameter:
SampleTime |
| Type: string scalar or character vector |
Default: "-1" |
